answer:Trade shows are good-- as an example, a relatively unknown company called Bluebeam has produced a competitor to Adobe Acrobat, but aimed specifically at the architecture market (has better markup capability, integrates better into Autocad, etc.)-- they handed out 30-day trials at the AIA convention. Our office now owns 10 licenses and has all but abandoned Acrobat, based entirely on the merits of the trial. Other options include direct marketing, door-to-door salesmanship, viral marketing, and getting a company to adopt your software at a great discount so word of mouth can spread... in the Bluebeam example above, I think we've gotten 2 or 3 other companies interested in it.